Golf club with unit-cell head construction

ABSTRACT

A golf club having a head wherein there is disposed a relatively strong but lightweight unit-cell structure portion between the head&#39;&#39;s toe and heel portions and immediately behind its generally planar impact face so that the weight of the head is concentrated at the toe, the toe and heel, or the toe, heel and sole portions in order to provide a relatively stiff and wider effective hitting area along with a relatively lower center of gravity, the unit-cell structure in an iron configuration, for example, including a plurality of parallel tubular elements extending generally perpendicular to the plane of the impact face.



1. A golf club, comprising: an elongated shaft having a lower end; and ahead having a hosel in an upper portion thereof, said lower end of saidshaft being fixedly disposed in said hosel, said head also having a toeportion and a heel portion and a generally planar high modulus impactface between said toe and heel portions, said head portion having hollowunit-cell structure means disposed therein immediately behind saidimpact face for broadening the effective hitting area of said impactface while reinforcing and enhancing the stiffness of said impact face,said unit-cell structure means including a plurality of interconnectedelongated unit-cells encapsulatEd by other interconnected elongatedunit-cells, each of the unitcells being defined by boundary cell walls,each boundary cell wall having a cross sectional thickness substantiallyless than the average of the largest and smallest external crosssectional dimension of the bounded unit cell, said boundary cell wallsextending generally rearwardly from and generally perpendicularly to theplane of said impact face.
 2. The golf club according to claim 1,wherein said unit-cell structure means is disposed in a hollowed outcavity portion of said head.
 3. The golf club according to claim 1,wherein said club is an iron and said unit-cell structure means isdisposed in a rearward exposed cavity section, said means extending froma rear surface situated immediately behind said impact face, said impactface and said rear surface defining a relatively thin impact walltherebetween.
 4. The golf club according to claim 3, wherein saidboundary cell walls define a honeycomb core structure.
 5. The golf clubaccording to claim 4, wherein said boundary cell walls of said honeycombcore structure have a hexagonal cross section.
 6. The golf clubaccording to claim 4, wherein said boundary cell walls of said honeycombcore structure have a rectangular cross section.
 7. The golf clubaccording to claim 4, wherein said boundary cell walls of said honeycombcore structure have a triangular cross section.
 8. The golf clubaccording to claim 4, wherein said boundary cell walls of said honeycombcore structure have a circular cross section.
 9. The golf club accordingto claim 1, wherein said club is a wood and the unit-cells define aplurality of elongated hollow bores in said head extending rearwardlyfrom a forwardly disposed impact plate, said impact face being the outersurface of said impact plate.
 10. The golf club according to claim 9,wherein said bores terminate at their rearward end in a common planedefining a rearward wall of said unit-cell structure means, and whereinsaid impact plate, said rearward wall and the bore configuration in saidhead define a sandwich honeycomb structure.
 11. The golf club accordingto claim 9, wherein said hollow bores have a generally circular crosssection.
 12. The golf club according to claim 9, wherein said hollowbores have a generally ellipsoid cross section.
 13. The golf clubaccording to claim 9, wherein said bores have differing cross sectionaldimensions.
 14. The golf club according to claim 1, wherein said club isa wood and said head includes a cavity therein, said unit-cell structuremeans being at least partially disposed therein.
 15. The golf clubaccording to claim 14, wherein said unit-cell structure means includes aface plate and wherein the unit-cells of said unit-cell structure meansdefine a prefabricated honeycomb core structure disposed in said cavitythe rearward end of which being bonded to the rearward wall of saidcavity and the forward end of which being bonded to the inner wall ofsaid face plate to define a sandwich honeycomb structure.
 16. The golfclub according to claim 15, wherein said boundary cell walls of theunit-cells define in cross section a curved geometric pattern.
 17. Theclub according to claim 15, wherein said boundary cell walls of theunit-cells define in cross section a multiple straight sided geometricpattern.
 18. The golf club according to claim 14, wherein the unit-cellsof said unit cell structure means define a prefabricated honeycomb corestructure disposed in said cavity the rearward end of which being bondedto the rear wall of said cavity and the forward end of said corestructure being spaced from and behind said impact face, said corestructure including a barrier wall disposed transversely to thelongitudinal axis of said core structure and spaced a relatively shortdistance behind said forward end of said core structure, said impactface being of a relatively hard plastic material that extends into saidcore structure only to sAid barrier wall.